1. Field
The invention relates to wood and coal burning heating units having a heat collecting jacket surrounding the combustion chamber and a means for forcing air through the jacket and into a room.
2. State of the Art
Heating units adapted for burning wood or coal are well known and in common use. Such units may consist of a combustion chamber having an air heating jacket juxtaposed at least a portion of the firebox. Room air is heated by being circulated through the heating jacket.
U.S. Pat. Nos. 1,681,449; 2,134,935; 2,743,720; and 3,981,292 each disclose hot air circulating systems comprising a jacket at the rear of the firebox, with conduits or a second jacket at the top of the firebox in communication with the jacket at the rear of the firebox. Air flows from the jacket at the rear of the firebox, through the conduits or second jacket at the top of the firebox and into the room which is to be heated.
U.S. Pat. No. 4,092,976 discloses a heating unit comprising a firebox having double walls at its back, sides and bottom and a single wall at its top and front. A fan is provided in the back wall for forcing air through the air channels formed by the double walled sections of the heating unit. Baffles are provided in the air channels to direct the forced air from the fan to vents in the front of the heating unit.